Mass number of element
20 to 40
(not in points )
If you don't know than please don't give Answer
who will give right Answer I will mark them brilliant and give thanks also.
Answers
1.0079 Hydrogen H 1
- 4.0026 Helium Hl
6.941 Lithium Li 3
9.012
2 Beryllium Be 4
- Electronegativity 10.811 Boron B 5
12.0107 Carbon C 6
14.0067 Nitrogen N 7
15.9994 Oxygen O 8
18.9984 Fluorine F 9
20.1797 Neon Ne 10
22.9897 Sodium Na 11
24.305 Magnesium Mg 12
26.9815 Aluminum Al 13
28.0855 Silicon Si 14
30.9738 Phosphorus P 15
The elements in water
32.065 Sulfur S 16
35.453 Chlorine Cl 17
39.0983 Potassium K 19
39.948 Argon Ar 18
40.078 Calcium Ca 20
44.9559 Scandium Sc 21
47.867 Titanium Ti 22
50.9415 Vanadium V 23
51.9961 Chromium Cr 24
54.938 Manganese Mn 25
55.845 Iron Fe 26
58.6934 Nickel Ni 28
58.9332 Cobalt Co 27
63.546 Copper Cu 29
65.39 Zinc Zn 30
69.723 Gallium Ga 31
72.64 Germanium Ge 32
74.9216 Arsenic As 33
78.96 Selenium Se 34
79.904 Bromine Br 35
83.8 Krypton Kr 36
85.4678 Rubidium Rb 37
87.62 Strontium Sr 38
88.9059 Yttrium Y 39
91.224 Zirconium Zr 40
92.9064 Niobium Nb 41
95.94 Molybdenum Mo 42
98 Technetium Tc 43
101.07 Ruthenium Ru 44
102.9055 Rhodium Rh 45
106.42 Palladium Pd 46
107.8682 Silver Ag 47
112.411 Cadmium Cd 48
114.818 Indium In 49
118.71 Tin Sn 50
121.76 Antimony Sb 51
126.9045 Iodine I 53
127.6 Tellurium Te 52
131.293 Xenon Xe 54
132.9055 Cesium Cs 55
137.327 Barium Ba 56
138.9055 Lanthanum La 57
140.116 Cerium Ce 58
140.9077 Praseodymium Pr 59
144.24 Neodymium Nd 60
145 Promethium Pm 61
150.36 Samarium Sm 62
151.964 Europium Eu 63
157.25 Gadolinium Gd 64
158.9253 Terbium Tb 65
162.5 Dysprosium Dy 66
164.9303 Holmium Ho 67
167.259 Erbium Er 68
168.9342 Thulium Tm 69
173.04 Ytterbium Yb 70
174.967 Lutetium Lu 71
178.49 Hafnium Hf 72
180.9479 Tantalum Ta 73
183.84 Tungsten W 74
186.207 Rhenium Re 75
190.23 Osmium Os 76
192.217 Iridium Ir 77
195.078 Platinum Pt 78
196.9665 Gold Au 79
200.59 Mercury Hg 80
204.3833 Thallium Tl 81
207.2 Lead Pb 82
208.9804 Bismuth Bi 83
209 Polonium Po 84
210 Astatine At 85
222 Radon Rn 86
223 Francium Fr 87
226 Radium Ra 88
227 Actinium Ac 89
231.0359 Protactinium Pa 91
232.0381 Thorium Th 90
237 Neptunium Np 93
238.0289 Uranium U 92
243 Americium Am 95
244 Plutonium Pu 94
247 Curium Cm 96
247 Berkelium Bk 97
251 Californium Cf 98
252 Einsteinium Es 99
257 Fermium Fm 100
258 Mendelevium Md 101
259 Nobelium No 102
261 Rutherfordium Rf 104
262 Lawrencium Lr 103
262 Dubnium Db 105
264 Bohrium Bh 107
266 Seaborgium Sg 106
268 Meitnerium Mt 109
272 Roentgenium Rg 111
277 Hassium Hs 108
Darmstadtium Ds 110
Copernicium Cn 112
Nihonium Nh 113
Flerovium Fl 114
Moscovium Mc 115
Livermorium Lv 116
Tennessine Ts 117
Oganesson Og 118
Explanation:
There are few simple rules to follow.
(1) The atomic number is equal to the number of protons.
Z
= number of protons
(2) In neutrally charged elements, the number of electrons is the same as the number of protons.
Z
= number of protons = number of electrons (no charge)
Otherwise, positive charge means that the element lost an electron and negative charge means it gained an electron.
(3) The atomic mass is equal to the sum of the number of protons and number of neutrons.
A
= number of protons + number neutrons
or
A
=
Z
+ number neutrons
So if you say that
Z
= 20 and
A
= 40, then
A
=
Z
+ number neutrons
40 = 20 + number of neutrons
40 - 20 = number of neutrons
Therefore,
number of neutrons = 20